ESD detection method for array substrate

ABSTRACT

The invention provides an ESD detection method for array substrate. By connecting the first metal layer on array substrate through the first wire to the first test point, connecting the second metal layer on array substrate through the second wire to the second test point, when ESD occurs on array substrate, the resistance detection device is used to measure the resistance between the first and second test points. If the resistance is positive infinity, ESD did not occur between the first and second metal layers; if the resistance is within a measurable range, ESD occurs between the first and second metal layers. The resistance is used to locate the location of ESD occurrence on array substrate. Compared to known method using microscope to search ESD location, the invention can locate ESD location on array substrate more accurately and rapidly to save time and labor as well as detection cost.

BACKGROUND OF THE INVENTION 1. Field of the Invention

The present invention relates to the field of display, and in particularto a electro-static discharge (ESD) detection method for arraysubstrate.

2. The Related Arts

The liquid crystal display (LCD) provides the advantages of thin, lowpower consumption, radiation-free, and so on, and is widely applied to,such as, mobile phones, personal digital assistant (PDA), digitalcamera, computer monitors and notebook computers.

The conventional liquid crystal display devices on the market are mostlyof the backlight type, comprising a case, a liquid crystal panel and abacklight module disposed inside the case. The traditional structure ofthe liquid crystal panel comprises a color filter (CF) substrate, a TFTarray substrate, and a liquid crystal layer sandwiched between twosubstrates. The working principle is to apply a driving voltage to thetwo glass substrates to control the rotation of the liquid crystalmolecules of the liquid crystal layer to refract the light frombacklight to display.

LTPS technology is a new generation TFT substrate manufacturingtechnology, and the major difference between the conventional amorphoussilicon (a-Si) technology and LTPS technology is that the LTPS providesthat advantages of high response speed, high brightness, high-resolutionand low power consumption.

As the LTPS TFT technology progresses, and due to the ultra-high carriermigration rate of LTPS semiconductor, the corresponding peripheralcircuits on the panel also attract attention from industry. Muchresearch is conducted on the system on panel (SOP) technology, whichgradually becomes a reality. Because the LTPS manufacturing is morecomplex and requires more processes, the probability of electro-staticdischarge (ESD) is higher.

ESD is a common process malfunction. When ESD occurs, the ESD-relatedcircuit will melt due to instantaneous high current. After cool down,the originally disconnected metal will be connected to further aggravatethe ESD damage. Therefore, ESD detection method is vital and necessary.The current ESD detection is to search the ESD damage under themicroscope, which is not only time-consuming, but also costly.

It is desirable to provide an ESD detection method to address the aboveissue.

SUMMARY OF THE INVENTION

The object of the present invention is to provide an ESD detectionmethod, which is able to accurately detect the locations of ESDoccurrence on the array substrate.

To achieve the above object, the present invention provides an ESDdetection method, which comprises: Step 1: providing an array substratefor ESD detection, the array substrate being disposed with a first metallayer and a second metal layer; the first metal layer being connected toa first test point on the array substrate through a first wire, and thesecond metal layer being connected to a second test point on the arraysubstrate through a second wire; Step 2: providing a resistancedetection device, using the resistance detection device to test aresistance between the first test point and the second test point; ifthe resistance between the first test point and the second test point ispositive infinity, no ESD occurrence between the first metal layer andthe second metal layer; if the resistance between the first test pointand the second test point is within a measurable range, an ESDoccurrence existing between the first metal layer and the second metallayer; as such, the resistance measured between the first test point andthe second test point being used to locate the location of the ESDoccurrence on the array substrate.

The first metal layer and the second metal layer are on different layersof the array substrate.

An insulating layer is disposed between the first metal layer and thesecond metal layer.

The array substrate is a LTPS TFT substrate.

The first metal layer and the second metal layer are one of Mo, Al or Cuor stacked layers of the above.

The insulating layer is made of SiNx, SiOx or a combination of both.

The first wire and the second wire are both metal wires, and the firsttest point and the second test point are both metal blocks.

The first wire and the second wire are made of Cu or Al.

The first test point and the second test point are made of Cu or Al.

The present invention provides an ESD detection method, which comprises:Step 1: providing an array substrate for ESD detection, the arraysubstrate being disposed with a first metal layer and a second metallayer; the first metal layer being connected to a first test point onthe array substrate through a first wire, and the second metal layerbeing connected to a second test point on the array substrate through asecond wire; Step 2: providing a resistance detection device, using theresistance detection device to test a resistance between the first testpoint and the second test point; if the resistance between the firsttest point and the second test point is positive infinity, no ESDoccurrence between the first metal layer and the second metal layer; ifthe resistance between the first test point and the second test point iswithin a measurable range, an ESD occurrence existing between the firstmetal layer and the second metal layer; as such, the resistance measuredbetween the first test point and the second test point being used tolocate the location of the ESD occurrence on the array substrate;wherein the array substrate is a LTPS TFT substrate; wherein the firstmetal layer and the second metal layer are one of Mo, Al or Cu orstacked layers of the above; wherein the first wire and the second wireare both metal wires, and the first test point and the second test pointare both metal blocks.

Compared to the known techniques, the present invention provides thefollowing advantages: the present invention provides an ESD detectionmethod for array substrate. By connecting the first metal layer on thearray substrate through the first wire to the first test point, andconnecting the second metal layer on the array substrate through thesecond wire to the second test point, when an ESD occurs on the arraysubstrate, the resistance detection device is used to measure theresistance between the first test point and the second test point. Ifthe resistance is positive infinity, the ESD did not occur between thefirst metal layer and second metal layer; if the resistance is within ameasurable range, an ESD occurs between the first metal layer and thesecond metal layer. The resistance measured between the first test pointand the second test point is used to locate the location of the ESDoccurrence on the array substrate. Compared to known method usingmicroscope to search ESD location, the present invention can locate theESD location on the array substrate more accurately and rapidly to savetime and labor as well as detection cost.

BRIEF DESCRIPTION OF THE DRAWINGS

To make the technical solution of the embodiments according to thepresent invention, a brief description of the drawings that arenecessary for the illustration of the embodiments will be given asfollows. Apparently, the drawings described below show only exampleembodiments of the present invention and for those having ordinaryskills in the art, other drawings may be easily obtained from thesedrawings without paying any creative effort. In the drawings:

FIG. 1 is a schematic view showing the flowchart of the ESD detectionmethod for array substrate provided by an embodiment of the presentinvention;

FIG. 2 is a schematic view showing the Step 1 of the first embodiment ofthe ESD detection method for array substrate provided by an embodimentof the present invention;

FIG. 3 is a schematic view showing the first metal layer and the secondmetal layer on the array substrate provided in Step 1 of the firstembodiment of the ESD detection method for array substrate operatingunder a normal condition provided by an embodiment of the presentinvention;

FIG. 4 is a cross-sectional view showing the first metal layer and thesecond metal layer in FIG. 3;

FIG. 5 is a schematic view showing the first metal layer and the secondmetal layer after ESD in FIG. 3;

FIG. 6 is a cross-sectional view showing the first metal layer and thesecond metal layer in FIG. 5;

FIG. 7 is a schematic view showing the Step 1 of the second embodimentof the ESD detection method for array substrate provided by anembodiment of the present invention;

FIG. 8 is a schematic view showing the first metal layer and the secondmetal layer on the array substrate provided in Step 1 of the secondembodiment of the ESD detection method for array substrate operatingunder a normal condition provided by an embodiment of the presentinvention;

FIG. 9 is a schematic view showing the first metal layer and the secondmetal layer after ESD in FIG. 8;

FIG. 10 is a schematic view showing the Step 1 of the third embodimentof the ESD detection method for array substrate provided by anembodiment of the present invention;

FIG. 11 is a schematic view showing the first metal layer and the secondmetal layer on the array substrate provided in Step 1 of the thirdembodiment of the ESD detection method for array substrate operatingunder a normal condition provided by an embodiment of the presentinvention;

FIG. 12 is a schematic view showing the first metal layer and the secondmetal layer after ESD in FIG. 11.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

To further explain the technical means and effect of the presentinvention, the following refers to embodiments and drawings for detaileddescription.

Refer to FIG. 1, in combination with FIGS. 2-6. The present inventionprovides an ESD detection method, which comprises:

Step 1: as shown in FIG. 2, providing an array substrate for ESDdetection, the array substrate being disposed with a first metal layer11 and a second metal layer 12; the first metal layer 11 being connectedto a first test point 31 on the array substrate through a first wire 21,and the second metal layer 12 being connected to a second test point 32on the array substrate through a second wire 22.

Preferably, the first test point 31 and the second test point 32 areboth disposed on the surface of the peripheral area of the arraysubstrate.

Specifically, the array substrate is a LTPS TFT substrate.

Specifically, the first metal layer 11 and the second metal layer 12 areon different layers of the array substrate, and both the first metallayer 11 and the second metal layer 12 are of a block structure.

Specifically, the first metal layer 11 and the second metal layer 12 areone of Mo, Al or Cu or stacked layers of the above.

Specifically, an insulating layer 13 is disposed between the first metallayer 11 and the second metal layer 12.

Specifically, the insulating layer 13 is made of SiNx, SiOx or acombination of both.

Specifically, the first wire 21 and the second wire 22 are both metalwires, and the first test point 31 and the second test point 32 are bothmetal blocks.

Specifically, the first wire 21 and the second wire 22 are made of Cu orAl.

Specifically, the first test point 31 and the second test point 32 aremade of Cu or Al.

Step 2: providing a resistance detection device (not shown), using theresistance detection device to test a resistance between the first testpoint 31 and the second test point 32.

Refer to FIGS. 3-4. If the resistance between the first test point 31and the second test point 32 is positive infinity, the first metal layer11 and the second metal layer 12 are not connected by ESD occurrence.Refer to FIGS. 5-6. If the resistance between the first test point 31and the second test point 32 is within a measurable range, the firstmetal layer 11 and the second metal layer 12 are connected due to ESDoccurrence, and hence an ESD occurs between the first metal layer 11 andthe second metal layer 12. As such, the resistance measured between thefirst test point 31 and the second test point 32 can be used to locatethe location of the ESD occurrence on the array substrate.

Specifically, the resistance detection device is a multimeter or amegger, preferably a multimeter.

Refer to FIGS. 7-9 for the second embodiment of the ESD detection methodfor array substrate of the present invention. The second embodimentdiffers from the first embodiment in that: the first metal layer 11 andthe second metal layer 12 on the array substrate to be tested are bothof a wire stricture, and the remaining is the same as the firstembodiment, thus the description will not be repeated.

Refer to FIGS. 10-12 for the third embodiment of the ESD detectionmethod for array substrate of the present invention. The thirdembodiment differs from the first embodiment in that: the first metallayer 11 and the second metal layer 12 on the array substrate to betested are both on the same layer and of a wire stricture, and theremaining is the same as the first embodiment, thus the description willnot be repeated.

In summary, the present invention provides an ESD detection method forarray substrate. By connecting the first metal layer on the arraysubstrate through the first wire to the first test point, and connectingthe second metal layer on the array substrate through the second wire tothe second test point, when an ESD occurs on the array substrate, theresistance detection device is used to measure the resistance betweenthe first test point and the second test point. If the resistance ispositive infinity, the ESD did not occur between the first metal layerand second metal layer; if the resistance is within a measurable range,an ESD occurs between the first metal layer and the second metal layer.The resistance measured between the first test point and the second testpoint is used to locate the location of the ESD occurrence on the arraysubstrate. Compared to known method using microscope to search ESDlocation, the present invention can locate the ESD location on the arraysubstrate more accurately and rapidly to save time and labor as well asdetection cost

It should be noted that in the present disclosure the terms, such as,first, second are only for distinguishing an entity or operation fromanother entity or operation, and does not imply any specific relation ororder between the entities or operations. Also, the terms “comprises”,“include”, and other similar variations, do not exclude the inclusion ofother non-listed elements. Without further restrictions, the expression“comprises a . . . ” does not exclude other identical elements frompresence besides the listed elements.

Embodiments of the present invention have been described, but notintending to impose any unduly constraint to the appended claims. Anymodification of equivalent structure or equivalent process madeaccording to the disclosure and drawings of the present invention, orany application thereof, directly or indirectly, to other related fieldsof technique, is considered encompassed in the scope of protectiondefined by the claims of the present invention.

What is claimed is:
 1. An electrostatic discharge (ESD) detectionmethod, which comprises: Step 1: providing an array substrate for ESDdetection, the array substrate being disposed with a first metal layerand a second metal layer, which are set in a first condition of beingspaced and isolated from each other by an insulating layer arranged at apredetermined location of the array substrate; the first metal layerbeing connected to a first test point on the array substrate through afirst wire, and the second metal layer being connected to a second testpoint on the array substrate through a second wire; Step 2: providing aresistance detection device, using the resistance detection device tomeasure a resistance between the first test point and the second testpoint; wherein an ESD occurring between the first metal layer and thesecond metal layer causes the first metal layer and the second metallayer to change from the first condition to a second condition in whichthe first metal layer and the second metal layer extend through theinsulating layer to connect with each other at the predeterminedlocation of the array substrate, so that the resistance measured betweenthe first test point and the second test point is within a predeterminedrange and the ESD occurring at the predetermined location on the arraysubstrate is identified.
 2. The ESD detection method as claimed in claim1, wherein the first metal layer and the second metal layer are ondifferent layers of the array substrate.
 3. The ESD detection method asclaimed in claim 2, wherein the insulating layer is disposed between thefirst metal layer and the second metal layer.
 4. The ESD detectionmethod as claimed in claim 1, wherein the first metal layer and thesecond metal layer are on the same layer of the array substrate.
 5. TheESD detection method as claimed in claim 1, wherein the array substrateis a low temperature polysilicon (LTPS) thin film transistor (TFT)substrate.
 6. The ESD detection method as claimed in claim 1, whereinthe first metal layer and the second metal layer are one of Mo, Al or Cuor stacked layers of the above.
 7. The ESD detection method as claimedin claim 3, wherein the insulating layer is made of SiNx, SiOx or acombination of both.
 8. The ESD detection method as claimed in claim 1,wherein the first wire and the second wire are both metal wires, and thefirst test point and the second test point are both metal blocks.
 9. TheESD detection method as claimed in claim 8, wherein the first wire andthe second wire are made of Cu or Al.
 10. The ESD detection method asclaimed in claim 8, wherein the first test point and the second testpoint are made of Cu or Al.
 11. An electrostatic discharge (ESD)detection method, which comprises: Step 1: providing an array substratefor ESD detection, the array substrate being disposed with a first metallayer and a second metal layer, which are set in a first condition ofbeing spaced and isolated from each other by an insulating layerarranged at a predetermined location of the array substrate; the firstmetal layer being connected to a first test point on the array substratethrough a first wire, and the second metal layer being connected to asecond test point on the array substrate through a second wire; Step 2:providing a resistance detection device, using the resistance detectiondevice to measure a resistance between the first test point and thesecond test point; wherein an ESD occurring between the first metallayer and the second metal layer causes the first metal layer and thesecond metal layer to change from the first condition to a secondcondition in which the first metal layer and the second metal layerextend through the insulating layer to connect with each other at thepredetermined location of the array substrate, so that the resistancemeasured between the first test point and the second test point iswithin a predetermined range and the ESD occurring at the predeterminedlocation on the array substrate is identified; wherein the arraysubstrate is a low temperature polysilicon (LTPS) thin film transistor(TFT) substrate; wherein the first metal layer and the second metallayer are one of Mo, Al or Cu or stacked layers of the above; andwherein the first wire and the second wire are both metal wires, and thefirst test point and the second test point are both metal blocks. 12.The ESD detection method as claimed in claim 11, wherein the first metallayer and the second metal layer are on different layers of the arraysubstrate.
 13. The ESD detection method as claimed in claim 12, whereinthe insulating layer is disposed between the first metal layer and thesecond metal layer.
 14. The ESD detection method as claimed in claim 11,wherein the first metal layer and the second metal layer are on the samelayer of the array substrate.
 15. The ESD detection method as claimed inclaim 13, wherein the insulating layer is made of SiNx, SiOx or acombination of both.
 16. The ESD detection method as claimed in claim11, wherein the first wire and the second wire are made of Cu or Al. 17.The ESD detection method as claimed in claim 11, wherein the first testpoint and the second test point are made of Cu or Al.